With increasing population concentration in most suburban and urban areas it is necessary to collect the sewage from the individual residential, commercial and business sewage outflows and process it at a central location. At the central treatment plant the sewage is treated to various stages allowing the resulting product to pass back into the ecological system. If left untreated certain types of sewage outflows are too high in organic matter such as grease, such that the organic matter will clog the collection system at one or more points prior to the sewage reaching the primary sewage treatment plant and be essentially so indigestible by the bacteria present that it must be skimmed off and discarded in bulk after collection. With increases in population, present sewage treatment facilities are unable to process the increased volume of organic matter in the flow without significant capital investment in new equipment.
Along the sewage transport lines to the treatment plant pumping stations are frequently located to transport the sewage to a higher elevation. These grease traps, lift stations and wet well locations serve as a collection point for grease and other organic matter that is not decomposed within the water flow. It is a common necessity to clean out these areas at a pumping stations or other junction points in the systems where floating grease and organic matter collects, hardens and remains there until it is removed by a pump to a truck. Lines with low flow rates, bends, and changes in elevations are also prone to build up organic deposits.
Most states and municipalities have placed limitations on the quantities of oil and grease which may be introduced into the municipal sewage collection system. Most businesses and industrial companies generating grease in quantity and are required to install a grease trap on the premises to collect the grease and prevent the bulk of it from entering the collection system. The grease collects in the trap until it is removed by hand or with a pump truck.
Recently, a partial answer to the problem of frequent removal and trucking away of the grease has been provided by the use of bacterial augmentation to maximize the effectiveness of organic decomposition. A bacterial supplement of highly cultured strains of bacteria with an exceptionally high capacity for specific organic reduction are charged into the sewage system. These bacteria are designed to reduce the grease and convert it to lower molecular weight compounds which will not accumulate within the downstream sewage collection system. These bacteria operate almost exclusively in the water phase and their cultures grow in the grease and water interface, on the sides and on the bottom of the tank or trap in which they are placed.
In addition, alien bacteria which compete with the supplemental bacteria constantly enter the system with fresh sewage. As a result, the highly cultured bacteria must be added frequently, often daily. Current methods of daily treatment rely on pumping in liquid bacteria that require expensive dispensing equipment that take up needed space at the area of induction. Often these liquid systems contain less bacteria than powder forms of bacteria containing the same bacteria, because these counts are lower the reduction of grease and organic matter requires more retention time and are more sensitive to inductions of chlorine, quaternary ammonium compounds, iodine, hot water, and other disinfectant material that are used to clean and disinfect in the facilities that release the waste water and raw sewage.
The device of parent U.S. patent application Ser. No. 08/984,475, filed Dec. 3, 1997, now U.S. Pat. No. 5,925,252 issued Jul. 20, 1999, provides a bioremediation device comprising a bioactive element having at least one active ingredient present in a variable concentration, the variable concentration being greatest substantially at the outside of said element and being least within the element, so that the bioremediation effect of the element is greatest when the waste material is first exposed to the outside of the element and lessons while the element dissolves in the waste materials, whereby the outside of the bioactive element has a relatively great bioactive effect for remediating the waste material and the inside of the bioactive element has a relatively lesser bioremediating effect for maintaining the waste material in the collection system. This device may thereby initially reduce the grease and other organic materials in the collection system and then maintain the remediation effect in the collection system. The present invention, which is a continuation-in-part of the prior application, may include similar structure and compositions, with additional or substitute structure and function relating to emulsification.